1. Field of the Invention
The present invention relates to an improved infrared radiation gas analyzer.
2. Description of the Prior Art
An infrared radiation gas analyzer as shown in FIG. 2 is one known apparatus for determining gas concentration. In a gas analyzer of such type, the principle that gaseous molecules other than mono-atomic molecules radiate infrared rays having a wave length peculiar to the gaseous molecules when heated at higher temperatures is utilized, a sample gas being introduced into a sample cell (1), the sample gas being heated by means of heaters (2) and (2') mounted on said sample cell (1), the radiated infrared rays being detected by an infrared ray detector (3), and the concentration of the component to be measured in the sample gas being determined on the basis of the dose of infrared rays. (5) designates a chopper used as modulation means.
In the conventional infrared gas analyzer of this type, since said heaters (2) and (2') are used in combination with a temperature controller (4) using a relay and the like therein and are adapted to be held at the desired temperatures by the ON-OFF action of said temperature controller (4), the gas analyzer has been subjected to a temperature-rippling to produce a drift and noise, whereby it has been difficult to carry out a highly accurate determination in a stable fashion.